Ragweed allergy is a relatively simple model with one known major allergen. Many patients are allergic to multiple pollens, each of which has several important allergens. Other questions include whether the AIC vaccine technique will be successful in treating more complicated allergens, such as mold, and whether this technique can be applied to polysensitized patients in whom some of the allergens are less well characterized than ragweed, Dr. Khan said.
Explore This IssueJanuary 2007
He also noted that the safety of AIC is a definite plus. “The dose of ragweed allergen used in the study would be considered a high dose for conventional immunotherapy and yielded not systemic reactions. Improvement with conventional allergen immunotherapy, is dose-dependent, but with a higher dose there are more side effects. This may not be the case with AIC, and perhaps even higher, more effective doses could be administered,” he explained.
Proof of Concept
According to William K. Dolen, MD, President of the American College of Asthma, Allergy and Immunology and Professor of Pediatrics and Medicine at the Medical College of Georgia in Augusta, Ga., the most important take-home message is that the pilot study represents proof of concept. “Scientifically, this is very exciting. The authors studied a specially designed vaccine that interacts with specific and nonspecific parts of the immune system. It is impressive that they were able to show an effect in such a small study,” Dr. Dolen said. He added that more data are needed to interpret the study results more closely. For example, there were no data on whether study participants had symptoms other times of the year in addition to the fall or whether they had other allergies.
Dr. Dolen doubted that the AIC vaccine would be available for general use any time soon because there are so many hurdles to cross. For one thing, the average patient on allergy shots is given multiple injections containing as many as 20 different pollens. “This is a single study of one component of one pollen from one plant. To be clinically useful, vaccines would have to be developed to attack multiple pollens, as well as dust mites, animal danders, and molds. It will take a long time to develop those vaccines,” he said. Additionally, the FDA approval process is lengthy and takes years.
©2007 The Triological Society